package com.foreknow.demo;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;

/**
 * 1. 要有继承或实现关系
 * 2. 方法重写
 * 3. 父类的引用指向子类的对象
 */
public class TestIO {
    public static void main(String[] args) throws FileNotFoundException {
        FileReader fileReader = new FileReader("");
        BufferedReader bufferedReader = new BufferedReader(fileReader);
    }
}
